Electric-circuit closer and breaker.



T; E. MoQUOWN. ELECTRIC CIRCUIT CLOSER. AND BREAKER AIPLIGATION FILEDNIOV; 24, 1906.

1,109,689 hten'ted Sept. 8, 1914.

nu/f if I) UTE STATES PATENT @FFFLCE.

THOMAS H. MOQUOWN, OF CAMBRIDGE. MASSACHUSETTS, ASSIGNOR. BY DIRECT ANDMESNE ASSIGNMENTS, SYLVANIA.

'10 ARTHUR AT'WATER KENT, OF PHILADELPHIA, PENN- ELECTRIC-CIRCUIT CLOSERAND BREAKER.

specification of Letters Patent.

llatented Sept. 8, 1914-.

To all ill/1,0777, it may concern Be it known that l, Tnoams H. MoQUowN,a citizen of the United States, and resident of Cambridge, county oflvliddlesex, State of ll iassachusetts, have invented an improvement inElectric-Circuit Closers and Breakers, of which the followingdescription. in connection with the accompanying drawing, is aspecification, like letters on the drawing representing like parts.

This invention relates to a device formaking and breaki g an electriccircuit. Dcvices of this character are commonly used in quite a varietyof mechanism, such for instance as electric time recorders, electricspeed recorders, ignition devices for internal combustion engines, etc.

In most of these mechanisms it is necessary to close the circuitmomentarily only, the mere closing and breaking of the circuit servingto operate the mechanism with which the make-and-break device is used,and in order to prevent any unnecessary consumption of current it isdesirable that as soon as the circuit has been closed it should beinstantly opened again.

A device which is adapted to break the circuit instantly that it isclosed is shown in my prior Reissued Patent No. 12,273, reissued October11, 1904.

In order to get the best result from these makc-and-brcak devices it isalso desirable that during the short interval of time that the contactsare closed together there should be a good electrical contact betweenthe contacts, and also that when they are separated to break the circuitthe separation should be instantaneous.

The necessary good electric contact can usually be produced by bringingthe contacts together with some little ressure, but 1n order to get thebest sparking effect where the circuit is broken it is desirable toseparate the contacts instantly while they are still underpressurerather than to separate them in such a way that'thepressurebetween them will gradually diminish to zero andthereafter thecontacts begin to open :1 art. p

.make-and-break device in which the contacts "are not only brokeninstantly that the circuit In my present invention I have provided a isclosed, but one in which the separation of the contacts occursinstantaneously from a closed condition in which they are pressedtogether with some force. This result is preferably secured by soconstructing one of the contacts that it constantly acted upon by someforce which tends to move it to\ aid the other contact, so that when thelatter contact is moved against the first contact to close the circuitthe contacts are held together bythis force. and when the contactsseparate to break the circuit the separation occurs instantancmisly at atime when they are thus pressed together. One convenient way ofaccoimilishing this result is to cmploy a spring of equivalent devicewhich constantly acts on one contact to move it toward the other, themovement of said first contact toward the other being limited by asuitable stop. lVhcn said other contact is closed against the firstcontact to close the circuit the two contacts are pressed together byaction of the spring. thus making the necessary good electrical contact,and when the latter contact moves away from the for mer the breaking orseparation occurs while they are thus pressed together thus producingthe desirable instantaneous break.

My invention may be embodied in various devices. and in order toillustrate it I have shown it as embodied in a make-and-br*ak device fora ships log. The invention however is not limited to use in connectionwith such an aiparatus as will be obvious.

in the rawings l igure 1 is a perspective view showing a ships logembodying my invention; Fig. 2 is a View of the casing for the a)paratus with the cover removed showing the make and break device; Fig.3 is a detail of the contact-closing member; Fig.

4 is a detail of the make-and-break device;

Fig. 5 shows another modification of the invention; Fig. (3 is a sectionthrough the post or stud 5.

Referring first to Figs. 2, 3 and d, the two contacts of themake-and-break device are designated by 3 and l, andin order to avoidconfusion I will refer to the contact 3 as the fixed contact and tocontact 4 as the movable contact. It will be understood however that thefixed contact 3 is not necessarily an absolutely rigid and unyieldingcontact but only one that is fixed relative to the contact 4 which movestoward and from the contact l 3. The fixed contact 3 is shown as an armis acted upon by means suclr'for instance as spring 6 which normallytends to force it toward the movable contact.

In the embodiment of the invention herein illustrated the spring 6 hasone end coiled around and secured to the stud 5 and the other end bentto engage the upper side of the contact 3. With this arrangement thespring will tend to swingthc contact 3 downwardly toward the contact 4.;its movement in this direction is limited by a suitable stop 8 which maybe in the form of a. pin projecting 'lron'rthe backing piece 9 on whichthe contact is mounted.

The movable contact t is shown as pivoted on a stud 10 which alsoextends from the backing piece 9, and preferably it will be acted uponby a suitable spring 11 tending to move it away from the contact 12- isa stop which serves to limit the downward movement of the contact at.lVith this construction it will be seen that the sprlngo acts to holdthe contact 3 against the stop 8 with more or less pressure dependingupon the resiliency of the spring 6.

If the movable contact i is moved upwardly sutliciently to engage thefixed contact 3 and lift it from the stop 8 the contacts will.be heldtogether by the pressure due to the action of the spring 6, which issuiiicient to furnish a good electrical contact between said contacts.This pressure will be maintained While said contacts are closedtogether.

When the movable contact 4: swings downwardly the fixed contact 3 willfollow it, said contacts still beingpressed together by the action ofthe spring 6 until the contact 3 rests against the stop 8 when thepressure with which the contacts are held together is instantly removedand the separation of the contacts occurs instantaneously and while theyare still under pressure. I

The means herein shown for giving move ment to the movable contact 4 isof such a construction that the two contacts will be broken instantlythat they are closed. The movable contact 4 is given its closingmovement by means of a contact-closing member 12, herein shown as a camloosely mounted upon a stud or pivot 13. This contact-closing member isturned about its stud thereby to bring the cam portion thereof againstthe movable contact 4 to force the latter against the fixed contact 3,and suitable means are employed to accelerate the movement of thecontact-closing member at the time that it is about to engage, with themovable. contact so as to cause the contacts to be quickly closed andthen instantly opened.

The means herein shown for-actuating the contact-closing memberoomprisesa gear wheel 1 1: formed with a shoulder 15 which is adapted toengage a. pin 16 which extends loosely through a slot 18 in thecontact-clos ing member, and is carried by an an; 17 loosely carried bythe stud 13.

{llhearm 17 is acted upon by a suitable spring, .weight or otherautomatically operating means which tends to huh. it in the positionshown in Fig. I have herein shown for this purpose a weight 19 which ispivoted to the casing 20, as at 21, and which is link 22.

The operation of the parts thus tar do" scribed will be apparent tothose skilled in the art and is as follows: As the gear 14% rotates in.the direction oi the arrow (1., Fig. 3, the shoulder 15 engages the endof the pin 16 and carries s'aid pin and the arm 17 around with it and assaid pin. reaches the end of the slot 18 the cauitact-closing menr ber12 is also carried around with the gear. When the arm 17 has beencarried around slightly past its vertical position, as shown in Fig. 4,the action of the weight 19 will tend to accelerate the movement oi thearm 17 and carry it quickly into the position shown in Fig. 2, andbecause the pin 16 extends through the slot in the member 12 themovement of the contact-closing member 12 is accelerated. Theacceleration oi the contact-closing member occurs ust prior to the timethat it engages the movable contact 4-, and the result is that theaccelerated movement of the contact-closing member 1'). carries saidmember out from engag ment with the movable contact l almostiils'itantly that, it is brought into engagement therewith. The contactsare thus vermitted to separate almost instantly that they are cl sed.During the accelerated movement oi the arm 17 the pin 16 thereof iscarried ahead of the shoulder 15 as will be obvious, and said pin shownin Fi 2, remain in sue position until during to rotation of the gear 14the shoulder 15 has again come in contact with the pin.

capable of operating when the gear 14 turns in either direction,andaccordmgly I have shown the gear 14 as having two opposed shoulders,one the shoulder 15 above described and the otherthe shoulder 25. Oneshoulder is operative when the gear is moving'in one direction and theother is opertive when the gear is movin in the opposite direction. Thecontact-closing member 12 is also made symmetrical in shape so that itmay operate in either direction. It de sired the movable contact 1 maycarry a friction roll 26 with which the contact-(low ing member engagesthereby to reduce the friction between the parts. In the presentembodiment of my invention this makeandbreak device is shown as used inconjunction with a ships log, and it accordingly is so mounted that thegear 11 may he turned connected to the pin 16 by means of a and arm 17will, after reachin Y the position- It is desirable to make themechanism by a usual rotator which drags through the water and operatesthe log.

The operative parts are inclosed in a suitable casing 20 which is shownas having a hollow stem 27 extending therefrom through which extends andin which is journaled a shaft 28 to which the line 29 leading to therotator is connected. This shaft 28 has fast thereon a pinion 30 whichmeshes with and drives the gear 14. The casing 20 is supported by auniversal joint device that it may swing both a vertical and horizontalaxis to permit it to accommodate itself to the motion of the vessel. Itis shown as pivoted to the arms 31 of a yoke device which in turn ispivoted to turn about a vertical stud 32 carried by a bracket 33. Thisbracket may be secured to any suitable portion of the vessel, as forinstance to the tafl rail 34. I have shown the stand 33 as detachablysecured to the taii'rails 34, it be ing removably supported by a basepiece 35 which is screwed to said tafi'rail.

'gThe complete device herein shown is gwadapted to be used in connectionwith some electrical recording device, such for instance as shown in myPatent No. 749,743, dated January 19, 1904, with which device thecontacts of the mechanism herein shown will be electrically connected.

It will be obvious of course that the contacts 3 and 4 must be insulatedfrom each other when they: are separated, and to accomplish this botharemounted upon a block 9 of insulating material, and the studs 5 and 10on which said contacts are mounted may extend through the insulatingmaterial and through the back of the case and constitute binding posts36 to which the wires of the circuit may be connected.

I have also shown a registering device mechanically connected with therotary shaft 28 so that the rotations of the shaft m'ay be read directlyfrom the casing 20 if desired. For this purpose the hub of the gear lthas thereon a worm 37 which meshes with and drives a worm gear on avertical,

shaft 38. Said shaft 38 has at its upper end another worm which mesheswith and drives a worm gear 39 on the shaft 40 of any suitableregistering device 41. The casing 20 is provided :with a removable cover42 which preferably has the sight opening 43 through which theregistering device 41 may be read.

In Fig.5? 5 I have shown another form of my invention in which the fixedcontact is made resilient, and the resiliency thereof is the force whichtends to move said contact toward the movable contact; In thisembodiment of my invention the fixed contact 300 is a resilent memberwhich is rigidly secured to its supporting member as at 301.

Said fixed contacts normally rest against a stop 800 which is sosituated that said movable contact when resting. thereagainst is undertension, the resiliency of "the fixed contact holding it against thestop with more or less pressure. The movable contact 400 may be movedagainst the fixed contact by any suitable means. It will be noted thatin this form of the invention when the movable contact during itsmovement engages the fixed contact 300 and lifts the same from its stop800 the resiliency of said fixed contact 300 holds the contacts togetherwith sufficient force to produce the necessary good electrical contactbetween them, and that as soon as the movable contact moves downwardlythis pressure is maintained until the fixed contact rests on the step800 when the contacts instantly separate thus breaking the circuit whilethe contact 300 is still under tension.

Having described my invention what I claim as new and desire to secureby Letters Patent is 1. in a make and break device the combination of ashaft, a wheel mounted on said shaft and rigidly secured theretoandcarrying a pair of oppositely arranged shouiders,

ders, a contact point, a movable support therefor, a symmetrical contactclosing member having an arc-shaped projection to operatively engagesaid support, said contact closing member being loosely mounted on saidshaft between said arm'and said wheel and provided with a slot throughwhich said pin extends; a stationary contact point arranged to cooperatewith said mentioned contact point, and yielding means also connected tosaid pin and acting on said arm immediateily prior to the instant thatsaid arc-shaped projection passes through a plane passing through thepoint of the operative engagement of said su port with said projectionand the axis of said shaft, to accelerate the movement of said contactclosing member.

2. In a contact device a shift, a crank arm loose on said shaft, a.crank pin extending parallel to said shaft, a cam loosely mounted onsaid shaft, the peripheral surface of which that is most remote from theaxis of said shaft being arc-shaped and extending concentrically to theaxis of said shaft, said cam being also provided with an arc-shaped slotalso concentric to the axis of said shaft andsymmetricaliy arranged withrespect to and on the same side of the axis of said shaft as saidarc-shaped surface or" said cam; a member rigidly secured to said shaftand having a pair of shoulders, one on each side of said shaft, saidcrank pin extending from said arm through said arc-shaped slot and intothe path of and between said shoulders a contact point carrying arm inthe path of the projecting arc-shaped surface of said cam and moved awayfrom the axis of said shaft when operated upon by said cam, a springtending to force said arm' toward the axis of said shaft to move saidarm into its position nearest the axis of said shaft when said arm isnot being acted upon by said cam, a Contact point mounted. on saidcontact carrying arm, a fixed contact point coiiperating therewith, anda Weight connected to said crank pin and normally holding said crank pinin aiinement With the 1,1oa,ese

axis of said shaft and the pointoi: engzwemeat of said cam wiihsaidincvahie 00 i, support and on that side of the axis of ca' shaftdiametrically opposite to that 01': support.

In testimony whereof, I have signed my name to this specificatik'uu in{he presence oi: two subscribing witnesses,

THOMAS H. MCQUUWR.

Witnesses LOUIS C. SMITH, MARGARET A. DUNN.

